This invention relates to the field of medical devices, and more particularly to a balloon catheter having a reinforcing mandrel.
Catheters designed for intravascular procedures such as angioplasty have a number of desirable characteristics. Such catheters must be able to transmit force along the length of the catheter shaft to allow it to be pushed through the vasculature. However, the catheter shaft must also retain sufficient flexibility to allow it to track over a guidewire through the often tortuous vasculature. Additionally, the catheter also must be able to cross stenosed portions of the vascular anatomy.
To help meet the desire for a catheter having sufficient pushability and crossability, while maintaining trackability, prior art designs have supplemented polymer catheter shafts with a stiffening wire or mandrel. Other prior art designs have addressed these handling and performance issues by using materials of different stiffness for the proximal and distal portions of the catheter, and employing a high strength metallic proximal shaft section, commonly called a hypotube. To prevent kinking at the junction of these two materials, while maintaining trackability and pushability, some conventional designs have employed a stiffening wire to bridge the transition in catheter shaft material. Despite these attempts, prior art designs have suffered from various drawbacks. For example, support mandrels do not always transmit axial force effectively.
Accordingly, it would be a significant advance to provide a catheter having improved pushability and crossability while maintaining good trackability. This invention satisfies these and other needs.